authHttpInterceptorFn doesn't work with relative URLs

I have angular app, I followed the getting started guide to implement the login and noticed the authentication header isn’t present with the requests.

i just found out that the reason is that my allowedList had the absolute URL but all my endpoints has the relative path ex.:
Get(Id: string): Observable<Dto[]> { return this.http.get<Dto[]>(api/v1/dto/${Id}); }
when I modified the URL to have the absolute path to the endpoint I got the authentication heading added to the request.

I tried to use an interceptor to adjust API URLs to have the full path but that doesn’t seem to do it. Do I have to update all my endpoints for this to work! is there a better way ?

This took me many hours to figured out why it was not working.